@michcia well, what I can say for sure is your 5 year old cousin cannot exercise software freedom with respect to Linux
If we want to talk about software being free in a recipient-independent way, we'd need to somehow aggregate over all recipients, which requires a judgement call
You could say today it's "an average programmer", but in an ideal world it'd be "every adult" or even "every child past primary school", like we expect for reading natural language